Results 71 to 80 of about 11,844 (268)
Primordial black holes in Gauss-Bonnet gravity
Physics Letters BIn this paper, we investigate the production of primordial black holes (PBHs) during the preheating era. Indeed, the amplification of field fluctuations can lead to the amplification of curvature perturbations.
Brahim Asfour +4 more
doaj +1 more source
Is There a Cosmological Constant? [PDF]
The Astrophysical Journal, 1996 We present limits on the cosmological constant from the statistics of gravitational lenses using newly completed quasar surveys, new lens data, and a range of lens models. The formal limit is $λ_0 < 0.66$ at 95\% confidence in flat cosmologies, including the statistical uncertainties in the number of lenses, galaxies, quasars, and the parameters ...
openaire +2 more sources
Caring with forests: Human and more‐than‐human care in forest occupations in Germany
People and Nature, EarlyView.Abstract Drawing on ongoing ethnographic and participatory action research within forest occupations in Germany, this paper develops the concept of ‘caring with forests’ to theorise the mutual, multidimensional relationships of care that emerge between humans and more‐than‐human beings in environmental protest settings.
Sebastian Garbe
wiley +1 more source
The FAST Project - A Next Generation UHECR Observatory
EPJ Web of Conferences, 2017 We present a concept for large-area, low-cost detection of ultrahigh-energy cosmic rays (UHECRs) with a Fluorescence detector Array of Single-pixel Telescopes (FAST)b, addressing the requirements for the next generation of UHECR experiments.
Fujii Toshihiro +15 more
doaj +1 more source
Black hole shadow with a cosmological constant for cosmological observers
European Physical Journal C: Particles and Fields, 2019 We investigate the effect of the cosmological constant on the angular size of a black hole shadow. It is known that the accelerated expansion which is created by the cosmological constant changes the angular size of the black hole shadow for static ...
Javad T. Firouzjaee, Alireza Allahyari
doaj +1 more source
Proceedings of European Physical Society Europhysics Conference on High Energy Physics — PoS(EPS-HEP 2009), 2010 A brief overview of various branches of contemporary string cosmology is given with an emphasis on moduli stabilization, de Sitter vacua, inflation, cosmic strings and primordial gravitational waves.
openaire +1 more source
People and Nature, EarlyView.Abstract Despite an ever‐growing body of environmental laws, biodiversity loss and climate breakdown persist globally. This has prompted debate over whether existing legal regimes can be strengthened sufficiently to address these crises, or whether more transformative legal approaches are needed The concept of rights of nature, which is gaining ...
Maximilian Nawrath +3 more
wiley +1 more source
Care through cultivation: Indigenous Swidden agriculture as forest care
People and Nature, EarlyView.Abstract This paper argues that the agricultural practices of Bunong swidden cultivators in northeastern Cambodia constitute relational care for forests that is fundamentally misunderstood, misrecognized, and marginalized by dominant state policies, conservation, and development paradigms. Bringing together care theory, long‐term ethnographic research,
Esther Leemann
wiley +1 more source
Journal of High Energy PhysicsWe study the cosmological gravitational particle production (CGPP) of spin- 3 2 $$ \frac{3}{2} $$ particles during and after cosmic inflation, and map the parameter space that can realize the observed dark matter density in stable spin- 3 2 $$ \frac{3}{2}
Edward W. Kolb +3 more
doaj +1 more source
Exploring f(Q) gravity through model-independent reconstruction with genetic algorithms
Physics Letters BIn this paper, we use a machine learning technique, specifically genetic algorithms, to reconstruct the functional form of f(Q) gravity in a model-independent manner. To achieve this, we use Hubble measurements derived from cosmic chronometers and radial
Redouane El Ouardi +4 more
doaj +1 more source